2011 INFINITI QX56 power steering

EC-90
< ECU DIAGNOSIS INFORMATION >[VK56VD]
ECM
111
(R) 175
(B) Fuel injector driver power supply Input [Ignition switch: ON]
BATTERY VOLTAGE
(11 - 14 V)
11 2
(SB) 175
(B) Fuel injector driver power supply Input [Ignition switch: ON] BATTERY VOLTAGE
(11 - 14 V)
11 4 (B) — ECM ground — — —
11 5 (B) — ECM ground — — —
120 (Y) 175
(B) EVAP canister vent control valve Output [Ignition switch: ON] BATTERY VOLTAGE
(11 - 14 V)
122
(BR/ W) 175
(B) VVEL actuator motor relay abort
signal (VVEL control module)
Input [Ignition switch: ON] 0 V
123
(V/R) 175
(B) Throttle control mo
tor relay Output [Ignition switch: ON
→ OFF] 0 - 1.0 V
↓
BATTERY VOLTAGE
(11 - 14 V)
↓
0 V
[Ignition switch: ON] 0 - 1.0 V
125
(GR) 175
(B) Fuel pump control module
(FPCM)
Output[When cranking engine] 0 - 0.5 V
[Engine is running]
 Warm-up condition
0 - 4.0 V
126 (O) 129
(P/L) Accelerator pedal position sen-
sor 2
Input[Ignition switch: ON]
 Engine: Stopped
 Accelerator pedal: Fully released
0.28 - 0.48 V
[Ignition switch: ON]
 Engine: Stopped
 Accelerator pedal: Fully depressed 2.0 - 2.5 V
128 (Y) 130
(R) ASCD steering switch Input [Ignition switch: ON]
 ASCD steering switch: OFF
4 V
[Ignition switch: ON]
 MAIN switch: Pressed 0 V
[Ignition switch: ON]
 CANCEL switch: Pressed 1 V
[Ignition switch: ON]
 RESUME/ACCELERATE switch: Pressed 3 V
[Ignition switch: ON]
 SET/COAST switch: Pressed 2 V
Te r m i n a l N o .
(Wire color) Description
ConditionVa l u e
(Approx.)
+ – Signal name Input/
Output
JPBIA3344ZZ
Revision: 2010 May2011 QX56

ECM
EC-91
< ECU DIAGNOSIS INFORMATION > [VK56VD]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
128
(Y) 175
(B) ICC steering switch Input [Ignition switch: ON]
 ICC steering switch: OFF
4.2 V
[Ignition switch: ON]
 MAIN switch: Pressed 0 V
[Ignition switch: ON]
 CANCEL switch: Pressed 1.9 V
[Ignition switch: ON]
 RESUME/ACCELERATE switch: Pressed 3.7 V
[Ignition switch: ON]
 SET/COAST switch: Pressed 3.2 V
[Ignition switch: ON]
 DISTANCE switch: Pressed 2.6 V
[Ignition switch: ON]
 DYNAMIC DRIVER ASSISTANCE switch: Pressed 1.0 V
129
(P/L) —Sensor ground
(Accelerator pedal position sen-
sor 2)
—— —
130 (R) —Sensor ground
(ASCD steering switch/ICC
steering switch) —— —
131
(L/W) 129
(P/L) Sensor power supply
(Accelerator pedal position sen-
sor 2)
— [Ignition switch: ON] 5 V
133
(SB) 150
(R) Sensor power supply
(Refrigerant pressure sensor/
Battery current sensor/EVAP
control system pressure sensor)
— [Ignition switch: ON] 5 V
134
(V/W) 175
(B) Fuel temperature sensor Input
[Engine is running]
 Warm-up condition2.8 V
136 (W/
R) 140
(R/Y) Accelerator pedal position sen-
sor 1
Input[Ignition switch: ON]
 Engine: Stopped
 Accelerator pedal: Fully released
0.65 - 0.87 V
[Ignition switch: ON]
 Engine: Stopped
 Accelerator pedal: Fully depressed 4.3 - 4.8 V
137 (W/
G) 140
(R/Y) Sensor power supply
(Accelerator pedal position sen-
sor 1)
— [Ignition switch: ON] 5 V
138 (V) 150
(R) Battery current sensor Input [Engine is running]
 Battery: Fully charged*
2
 Idle speed2.6 - 3.5 V
139 (G) 175
(B) Battery temperature sensor Input [Engine is running]
 Battery temperature: 25
°C
 Idle speed 3.3 V
140
(R/Y) —Sensor ground
(Accelerator pedal position sen-
sor 1) —— —
141
(SB) 175
(B) Ignition switch Input [Ignition switch: OFF] 0 V
[Ignition switch: ON]
BATTERY VOLTAGE
(11 - 14 V)
Te r m i n a l N o .
(Wire color) Description
ConditionVa l u e
(Approx.)
+ – Signal name Input/
Output
Revision: 2010 May2011 QX56

EC-98
< ECU DIAGNOSIS INFORMATION >[VK56VD]
ECM
NOTE:
*: If “P1197” is displayed with other DTC in priority 1, perform trouble diagnosis for “P1197” first.
DTC IndexINFOID:0000000006217733
×
:Applicable —: Not applicable
2  P0031 P0032 P0051 P0052 Air fuel ratio (A/F) sensor 1 heater
 P0037 P0038 P0057 P0058 Heated oxygen sensor 2 heater
 P0075 P0081 Intake valve timing control solenoid valve
 P0130 P0131 P0132 P0133 P0150 P0151 P0152 P015 3 P2A00 P2A03 Air fuel ratio (A/F) sensor 1
 P0137 P0138 P0139 P0157 P0158 P0159 Heated oxygen sensor 2
 P0190 - P0193 FRP sensor
 P0441 EVAP control system purge flow monitoring
 P0443 P0444 P0445 EVAP canister purge volume control solenoid valve
 P0447 P0448 EVAP canister vent control valve
 P0451 P0452 P0453 EVAP control system pressure sensor
 P0550 Power steering pressure sensor
 P0603 ECM power supply
 P0710 P0717 P0720 P0729 P0730 P0731 P0732 P0733 P0734 P0735 P0740 P0744 P0745 P0750 P0775 P0780 P0795 P1730 P1734 P2713 P2722 P2731 P2807 A/T related sensors, solenoid valves and switches
 P1087 P1088 VVEL system
 P1090 P1093 VVEL actuator motor
 P1091 VVEL actuat or motor relay
 P1217 Engine over temperature (OVERHEAT)
 P1650 Starter motor relay 2
 P1651 Starter motor relay
 P2101 Electric throttle control function
 P2118 Throttle control motor
 P1805 Brake switch
 P2100 P2103 Throttle control motor relay
 P2101 Electric throttle control function
3  P0011 P0021 Intake valve timing control  P0087, P0088, P0090 FRP control system
 P008A Low fuel pressure control system
 P008B Low fuel pressure control system
 P0171 P0172 P0174 P0175 Fuel injection system function
 P0201 - P0208 Injector
 P0300 - P0308 Misfire
 P0420 P0430 Three way catalyst function
 P0456 EVAP control system (VERY SMALL LEAK)
 P0506 P0507 Idle speed control system
 P050E Cold start control
 P0524 Engine oil pressure
 P1148 P1168 Closed loop control
 P1212 TCS communication line
 P1421 Cold start control
 P1564 ASCD steering switch / ICC steering switch
 P1652 Starter motor system communication
 P2119 Electric throttle control actuator
 P1564 ASCD steering switch / ICC steering switch
 P1568 ICC command value
 P1572 ASCD brake switch / ICC brake switch
 P1574 ASCD vehicle speed sensor / ICC vehicle speed sensor
Priority Detected items (DTC)
DTC*1
Items
(CONSULT-III screen terms) SRT code Trip MIL
Reference
page
CONSULT-III
GST*
2ECM*3
U0101 0101 LOST COMM (TCM) — 1 ×EC-171
U0113 0113 CAN COMM CIRCUIT — 1 ×EC-173
U1001
1001*4CAN COMM CIRCUIT — 1 or 2 — EC-172
U1003 1003 CAN COMM CIRCUIT — 2 — EC-173
Revision: 2010 May2011 QX56

EC-166
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
TROUBLE DIAGNOSIS - SPECIFICATION VALUE
1. Check for the cause of large engine friction. Refer to the following.
- Engine oil level is too high
- Engine oil viscosity
- Belt tension of power steering, alternat
or, A/C compressor, etc. is excessive
- Noise from engine
- Noise from transmission, etc.
2. Check for the cause of insufficient combustion. Refer to the following.
- Valve clearance malfunction
- Intake valve timing control function malfunction
- Camshaft sprocket installation malfunction, etc.
>> Repair or replace malfunctioning part, and then GO TO 27.
16.CHECK INTAKE SYSTEM
Check for the cause of uneven air flow through mass air flow sensor. Refer to the following.
 Crushed air ducts
 Malfunctioning seal of air cleaner element
 Uneven dirt of air cleaner element
 Improper specification of intake air system
Is the inspection result normal?
YES >> GO TO 18.
NO >> Repair or replace malfunctioning part, and then GO TO 17.
17.CHECK “A/F ALPHA-B1”, “A/F ALPHA-B2” AND “B/FUEL SCHDL”
Select “A/F ALPHA-B1”, “A/F ALPHA-B2” and “B/FUE L SCHDL” in “SPEC” of “DATA MONITOR” mode, and
check that each indication is within the SP value.
Is the measurement value within the SP value?
YES >> INSPECTION END
NO >> “B/FUEL SCHDL” is more, “A/F ALPHA-B1” and “A /F ALPHA-B2” are less than the SP value: GO
TO 18.
18.DISCONNECT AND RECONNECT MASS AIR FLOW SENSOR HARNESS CONNECTOR
1. Stop the engine.
2. Disconnect mass air flow sensor harness connector. Check pin terminal and connector for damage and then reconnect it again.
>> GO TO 19.
19.CHECK “A/F ALPHA-B1” AND “A/F ALPHA-B2”
1. Start engine.
2. Select “A/F ALPHA-B1” and “A/F ALPHA-B2” in “ SPEC” of “DATA MONITOR” mode, and check that each
indication is within the SP value.
Is the measurement value within the SP value?
YES >> Detect malfunctioning part of mass air flow sensor circuit and repair it. Refer to EC-201, "Diagno-
sis Procedure". Then GO TO 26.
NO >> GO TO 20.
20.CHECK “MAS A/F SE-B1”
Select “MAS A/F SE-B1” in “SPEC” of “DATA MONITOR” mode, and check that the indication is within the SP
value.
Is the measurement value within the SP value?
YES >> GO TO 21.
NO >> More than the SP value: Replace malfuncti oning mass air flow sensor, and then GO TO 26.
21.REPLACE ECM
1. Replace ECM.
2. Perform EC-143, "
Work Procedure".
Revision: 2010 May2011 QX56

EC-276
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P0190, P0192,
P0193 FRP SENSOR
P0190, P0192, P0193 FRP SENSOR
DTC LogicINFOID:0000000006288295
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.PRECONDITIONING
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is 11 V or more at idle.
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE
1. Start the engine ON and wait at least 60 seconds.
2. Check DTC or 1st trip DTC.
Is DTC or 1st trip DTC detected?
YES >> Proceed to EC-276, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006288296
1.CHECK FRP SENSOR POWER SUPPLY-I
1. Turn ignition switch OFF.
2. Disconnect FRP sensor connector.
3. Turn ignition switch ON.
4. Check the voltage between FRP sensor harness connector terminals.
Inspection result normal?
YES >> GO TO 6.
NO >> GO TO 2.
2.CHECK FRP SENSOR POWER SUPPLY-II
Check the voltage between FRP sensor harness connector and the ground.
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0190 Fuel rail pressure sensor
circuit low input and high in-
put Signal voltage from the fuel rail pressure
sensor remains at more than 4.84 V /
less than 0.2 V for 5 seconds or more.  Harness or connectors
(Fuel rail pressure sensor circuit is open or
shorted.)
(Power steering pressure sensor circuit is
open or shorted.)
(Low fuel pressure sensor circuit is open or
shorted.)
(The electrically-controlled cooling fan cou-
pling circuit is open or shorted)
 Fuel rail pressure sensor
 Power steering pressure sensor
 Low fuel pressure sensor
 Electrically-controlled cooling fan coupling
P0192
Fuel rail pressure sensor
circuit low input Signal voltage from the fuel rail pressure
sensor remains at less than 0.37 V for 5
seconds or more.
P0193 Fuel rail pressure sensor
circuit high input Signal voltage from the fuel rail pressure
sensor remains at more than 3.46 V for 5
seconds or more.
FRP sensor
Voltag e
(Approx.)
Connector +
−
terminal
F26 1 3 5 V
Revision: 2010 May2011 QX56

P0190, P0192, P0193 FRP SENSOR
EC-277
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
Is inspection result normal?
YES >> GO TO 4.
NO >> GO TO 3.
3.CHECK SENSOR POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness connector for short to power and short to ground, between the following terminals.
Is inspection result normal?
YES >> Perform the trouble diagnosis for power supply circuit. Refer to EC-168, "Diagnosis Procedure".
NO >> Repair or replace error-detected parts.
4.CHECK FRP SENSOR GROUND CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check the continuity between FRP sens or harness connector and ECM harness connector.
Is inspection result normal?
YES >> GO TO 5.
NO >> Repair or replace error-detected parts.
5.CHECK ECM GROUND CIRCUIT
Check the continuity between ECM harness connector and the ground.
Is inspection result normal?
YES >> Check intermittent incident. Refer to GI-40, "Intermittent Incident".
NO >> Repair or replace error-detected parts.
+
−Vo l ta g e
(Approx.)
FRP sensor
Connector Terminal F26 1 Ground 5 V
ECM Sensor
Connector Terminal Name Connector Terminal
F 111 27Low fuel pressure sensor F25 3
Power steering pressure sensor F35 1
Cooling fan speed sensor F39 2
28 FRP sensor F26 1
+ −
Continuity
FRP sensor ECM
Connector Terminal Connector Terminal F26 3 F111 40 Existed
ECM Ground Continuity
Connector Terminal
F 111 5
Ground Existed
E80 11 4
11 5
174
175
Revision: 2010 May2011 QX56

P0191 FRP SENSOREC-279
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
P0191 FRP SENSOR
DTC LogicINFOID:0000000006288298
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.PRECONDITIONING
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is 11 V or more at idle.
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE
1. Start the engine and warm it up to the normal operating temperature. NOTE:
Warm up the engine until “COOLAN TEMP/S” on “DATA MONITOR” of CONSULT-III reaches at least
70 °C (158 °F).
2. Turn the ignition switch OFF and cool the engi ne until the engine coolant temperature reaches 35 °C
(95 °F) or less.
CAUTION:
 The difference between air temperature an d engine coolant temperature must be 5°C or less.
 Do not turn ignition switch ON.
3. Turn ignition switch ON and wait at least 60 seconds.
4. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Proceed to EC-279, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006288299
1.CHECK FRP SENSOR POWER SUPPLY-I
1. Turn ignition switch OFF.
2. Disconnect FRP sensor connector.
3. Turn ignition switch ON.
4. Check the voltage between FRP s ensor harness connector terminals.
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0191 Fuel rail pressure sensor Fuel rail pressure re
mains at more than
1.5 MPa (15 bar, 15.3 kg/cm
2, 217.5 psi)
for 0.2 seconds or more during ignition
ON.  Harness or connectors
(Fuel rail pressure sensor circuit is open or
shorted.)
(Power steering pressure sensor circuit is
open or shorted.)
(Low fuel pressure sensor circuit is open or
shorted.)
(The electrically-controlled cooling fan cou-
pling circuit is open or shorted)
 Fuel rail pressure sensor
 Power steering pressure sensor
 Low fuel pressure sensor
 Electrically-controlled cooling fan coupling
Revision: 2010 May2011 QX56

EC-280
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P0191 FRP SENSOR
Inspection result normal?
YES >> GO TO 6.
NO >> GO TO 2.
2.CHECK FRP SENSOR POWER SUPPLY-II
Check the voltage between FRP sensor harness connector and the ground.
Is inspection result normal?
YES >> GO TO 4.
NO >> GO TO 3.
3.CHECK SENSOR POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness connector for short to power and short to ground, between the following terminals.
Is inspection result normal?
YES >> Perform the trouble diagnosis for power supply circuit. Refer to EC-168, "Diagnosis Procedure".
NO >> Repair or replace error-detected parts.
4.CHECK FRP SENSOR GROUND CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check the continuity between FRP sens or harness connector and ECM harness connector.
Is inspection result normal?
YES >> GO TO 5.
NO >> Repair or replace error-detected parts.
5.CHECK ECM GROUND CIRCUIT
Check the continuity between ECM harness connector and the ground.
FRP sensor Voltag e
(Approx.)
Connector +
−
terminal
F26 1 3 5 V
+ −Voltag e
(Approx.)
FRP sensor
Connector Terminal F26 1 Ground 5 V
ECM Sensor
Connector Terminal Name Connector Terminal
F 111 27Low fuel pressure sensor F25 3
Power steering pressure sensor F35 1
Cooling fan speed sensor F39 2
28 FRP sensor F26 1
+ −
Continuity
FRP sensor ECM
Connector Terminal Connector Terminal F26 3 F111 40 Existed
Revision: 2010 May2011 QX56